The so-called Alan Author Effect is a surprising phenomenon in Bayesian Confirmation Theory. It occurs when a piece of evidence e confirms the conjunction of two hypotheses h1h2 but at the same time disconfirms each hypothesis h1 and h2 individually. In this paper, I present a new and prima facie stronger version of this effect where additionally, the evidence e confirms the conjunction of the negated hypotheses ¬h1¬h2. I say ‘prima facie’ because it can be shown that this seemingly stronger effect and the original effect are actually coextensional. I use this insight to formulate a new sufficient (and also necessary) condition for the two equivalent effects. I also examine how likely the two effects are to occur with the help of Monte Carlo simulation methods.

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